Config file cannot be parsed by unbound

[tonymorella]

When I make any changes to Unbound I am getting the following:
The generated config file cannot be parsed by unbound. Please correct the following errors:
/var/unbound/test/unbound_server.key: No such file or directory
[1480357537] unbound-checkconf[69057:0] fatal error: server-key-file: "/var/unbound/test/unbound_server.key" does not exist
This just started today, no changes I can think of caused this.

If I make the test directory and copy all the files from /var/unbound into it I am able to save changes and the test directory is deleted.

in unbound.inc can see the function in unbound.inc:

function test_unbound_config($unboundcfg, &$output) {
        global $g;

        $cfgsubdir = "/test";
        unbound_generate_config($unboundcfg, $cfgsubdir);
        unbound_remote_control_setup($cfgsubdir);
        do_as_unbound_user("unbound-anchor", $cfgsubdir);

        $cfgdir = "{$g['unbound_chroot_path']}{$cfgsubdir}";

        $rv = 0;
        exec("/usr/local/sbin/unbound-checkconf {$cfgdir}/unbound.conf 2>&1", $output, $rv);
        rmdir_recursive($cfgdir);

        return $rv;

Any ideas?

Update:

I just updated to dev 2.3.3 and the problem is gone, but not sure how stable this version is.